Units of measurement used in surveying & construction works

Unit of measurement is also known as the International System of Units, or SI. Units of measure in the metric system. The units of length or linear size are derived from the metre. They comprise of the kilometre (km) that is 1000 meters, the centimetre (cm), and the millimetre (mm) which is 1/1000th of a meter.

A unit of measurement refers to a specific magnitude of a quantity, described and approved by convention or by law, that is used as a standard for measurement of the same kind of quantity.

Any other quantity of that type can be stated as a multiple of the unit of measurement. As for instance, a length is a physical quantity.

Standard unit of measurement :-

Type – U.S. Unit – Metric Unit
Length – Inches, Feet, Yards, Miles – Millimeters, Centimeters, Meters, Kilometers
Weight – Ounces, Pounds – Grams, Kilograms
Time – Seconds, Minutes, Hours – Seconds, Minutes, Hours
Volume – Ounces, Gallons – Milliliters, Liters

Given below, the details of measurements which are utilized in surveying and construction works :-

For construction work: feet, inches, fractions of inches (m, mm)
For most surveys: feet, tenths, hundredths, thousandths (m, mm)

For National Geodetic Survey (NGS) control surveys: meters, 0.1, 0.01, 0.001 m

The following equivalents are used frequently :-
1 meter=39.37 in =3.2808 ft
1 rod =1 pole=1 perch=16.5ft(5.029 m)
1 engineer’s chain =100 ft =100 links (30.48 m)
1 Gunter’s chain= 66 ft (20.11 m) =100

Gunter’s links(lk)=4 rods=0.020 km
1 acre=100,000 sq (Gunter’s) links=43,560ft2 = 160 rods2 =10 sq (Gunter’s) chains=4046.87m2 = 0.4047 ha
1 rood=1011.5 m2 =40 rods2
1 ha= 10,000 m2 =107,639.10 ft2 = 2.471 acres
1 arpent=about 0.85 acre, or length of side of 1 square arpent (varies) (about 3439.1 m2)

1 statute mi=5280 ft=1609.35 m
1 mi2 = 640 acres (258.94 ha)
1 nautical mi (U.S.)= 6080.27 ft= 1853.248 m
1 fathom=6 ft (1.829 m)
1 cubit=18 in (0.457 m)
1 degree=0.01745 rad=60 min =3600 s
sin 1 =0.01745241
1 rad = 57.30 degree

For more information, go through the following link www.onlinecivilforum.com

Units of measurement used in surveying & construction works

Published By
Arka Roy



Detail lists of useful construction tools

Given below, the detailed lists of various useful construction tools and their applications :-

Hoe – It is effective for digging and arranging concrete, cement mortar in head pan. Hoe is also useful for excavating the soil but here the metal plate is set with acute angle to the wooden handle.

Head Pan – It is utilized to transmit materials. Head pan is built with iron to uprise the excavated soil or cement or concrete to the construction site etc. it is mostly found in construction sites.

Masonry trowel – The objective of this tool is to organize cement mortar. It refers to a hand trowel that is applied in brickwork or stonework for the purpose of leveling, dispersion and shaping mortar or concrete.

Measurement Tape – It is employed to examine the thickness, length, widths of masonry walls, foundation beds, excavated trenches etc.

Plumb Bob – It is applicable for verifying the vertical alignment of the structures. It comprises of a solid metal bob attached with the end of a thread. It can also be applied in surveying to level the instrument position.

Wheel Barrow – It is useful for carrying out cement mortar or any materials. Often, it is utilized to estimate the quantities of materials for site level concrete mixing.

Concrete Mixer – It is a machine that is used for blending the concrete perfectly with water, fine aggregate, coarse aggregate and cement at construction site.

Vibrator – It is utilized to vibrate the concrete when pouring is started. For the purpose of workability, water is added to concrete. To get rid of that, vibrators are applied.

Bump Cutter/Screed – The objective of this tool is to level fresh concrete surface particularly in slab concrete.

Wooden Float/wooden rendering float – This tool is useful for providing a flat finish to the plastered area.

Crow Bar – This tool is found in formwork to eliminate nails from boards. Crow bar is also applied for digging the ground and taking out the roots of trees in the ground, nails etc.

Framing Square – This tool is mostly found in Brickwork, Plastering to verify exact angle.

Line Level – This tool is required to verify horizontal level in brickwork, plastering , flooring and tile works.

Flat Pry Bar – This tool is found in shuttering and often utilized to modify the column formwork to align.

Digging bar – This tool is used to divide and unloose the compacted / hard surface area. Digging bar refers to a solid metal rod having pin shape at the bottom. It is also utilized to dig the hard surfaces of ground.

For more information, go through the following link www.civilology.com

Detail lists of useful construction tools

Published By
Arka Roy

Some handy tips to examine the quality of cement in the construction site

Cement is considered as the most vital component in any construction. The cement plays the role of a binder that unites aggregate and sand jointly in concrete.

Though it is difficult to examine all the properties of cement, but there are some elementary field tests which provide a rough idea about the quality of cement.

Given below, the detailed lists of simple tests which can be easily accomplished devoid any equipment to determine the cement quality. These elementary tests involve examining the properties of cement upon which the strength and quality of Cement depend.

1. Date of Packing (MFG Date): It is found that the strength of the cement decreases as time passes. According to IS Specifications, cement should be reexamined if it is preserved in excess of three months in the mill.

The percentage of strength loss for various time gapping is provided below.

From the above mentioned table, it is found that the strength of cement is reduced over a period of time.

2. Colour of Cement: The color of cement should have been consistent. Grey containing a light greenish shade is considered as a standard color of cement. The quantity of surplus clay or line is determined with cement color.

3. Check for lumps: If moisture exists in cement, lumps may develop. Cement endures a chemical reaction if it gets in touch with the atmospheric moisture and it is called as hydration. Moisture is very harmful for cement. Cement becomes ineffective as soon as it is hydrated with water (liquid form or vapour form)

4. Rubbing Test: Choose a bit of cement rub within your fingers, if it remains smooth at the time of rubbing, the quality of cement is good. But if it is rough, it signifies that cement is blended with sand.

5. Float test of cement: Choose a bit of cement and put it in water, a good quality of Cement should be submerged and should not float on water.

6. Hand insertion: Put your hand into the cement bag. It you get cool feeling, then there is no hydration reaction in cement bag.

For more information, go through the following link civilread.com

Some handy tips to examine the quality of cement in the construction site

Published By
Arka Roy

How to estimate cement bags in 1 cubic meter

Suppose the proportion of nominal mix is 1:2:4 (one part cement, 2 part sand and 4 part aggregate)

Wastage of cement is taken as 2%
Output of mix is provided as 67%.

For 1 cum output, the requirement of dry mix is 1/0.67 = 1.49 say 1.50 cum.
After including the wastage (2%), the output will be (1.50 + 0.02) = 1.52 cum.
Volume of cement = (cement/cement+sand+aggregate) × Total material

= (1/1+2+4) × 1.52
=0.2171 cum
The density of cement is 1440 kg/cum and
Weight of 1 bag cement = 50 kg.

So, volume of 1 bag cement = 50/1440
=0.0347 cum.
No. of cement bags essential in 1 cubic meter = 0.2171/0.0347
= 6.25 bags.
The above formula can be utilized for measuring cement for other nominal mixes.

To get more details, watch the following video tutorial.

How to estimate cement bags in 1 cubic meter

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Arka Roy


How to make calculation for rebar with Rebarcalculator

Rebarcalculator is used for making calculations/conversions of rebar from weight(MT), Surface are(M2), No. of bar(12 meter length each) and total Length(meter) in any combinations.

To compute from Weight(MT) and transform it into Surface are(M2). As for instance Dia 10 MM & Quantity 5 MT, choose the unit MT from green panel and then opt for the convertible unit as output ie. M2 from Blue panel. Press calculate to obtain the required conversion.

It is mostly effective for site engineers, Managers, Project leaders in rolling, civil construction and coating industry to calculate cost and operational detail.

If you find this is useful, please comment on my blog and suggest of similar or any other areas in your business which can be improved with such software/applications.

One can access Rebarcalculator at free of cost. It is compatible with windows but does not support Mac OS X, Linux, Solaris, FreeBSD, or AIX.

Online Rebar Calculator

To get more details, watch the following video tutorial.

Video Source: Calculated Industries

How to make calculation for rebar with Rebarcalculator

Published By
Arka Roy


Pros and Cons of a cavity wall Construction

Cavity wall made of double walls and a hollow space exists among them. A wall that is built up with two leaves or skins having a space or cavity among them is titled as a cavity wall. It is generally developed as an outside wall.

Cavity wall thickness of an outside wall and inside wall are equivalent or the inner wall may be deeper as compared to the outer wall. Cavity wall hollow never surpasses 100mm and it is consistent through the height.

The objective of building up a cavity wall is to resist the infiltration of rain to the inner surface of the wall. It is indispensable that cavity walls should not be bridged in any way as this would deliver a passage of moisture.

The masonry skins of a cavity wall belong to brickwork, blockwork or similar. Various types of masonry materials are applied on either side of the cavity. The cavity is primarily empty but is filled with insulation through several methods.

Lots of times are required to build up cavity walls and so little bit expensive to construct as compared to walls having the two skins bonded together. But they have good sound resistance capacity and come with superior sound and heat insulation and most significantly resistance to rain infiltration.

To maintain the longevity, strength and appearance, a damp resistant course of brick or block should be used for building up the cavity wall above ground level.

To resolve this issue, it is required to fill the cavity underneath ground level with a weak mix of concrete so that a solid wall is formed on the ground.

Benefits of cavity wall construction: Damp Prevention: Cavity wall controls the prevention of dampness from outer surface to interior of the building in an efficient manner as compared to a solid brick wall of the similar thickness.

Heat Insulation: As air is a bad conductor of heat, a cavity wall reduces the heat transmission significantly to sustain unvarying temperature inside the building.

Sound Insulation: Sound waves can move rapidly in solid media relating to air, the cavity wall constructions significantly reduces the noise from outside as well as inside the building to get rid of external disturbances.

Economical: The construction cost of a cavity wall is about 20% less than the construction cost of a solid wall having the same thickness.

It has the capability to resist a driving rain in all situations from entering to the inner wall.

Drawbacks of cavity walls

a. A high standard of design and workmanship is required to make a good construction wall
b. Good supervision is necessary throughout construction.
c. The requirement of a vertical damp proof course to all openings
d. The construction cost is little higher as compared to a standard one brick thick wall.

To gather more information, click the following link.constructiontuts.com

Pros and Cons of a cavity wall

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Arka Roy

How to create rate analysis of civil works

Each construction project is segregated into various numbers of activities. Each activity is supported with types of civil or construction works.

As for instance, when a building is constructed there are various activities like excavation or earthwork, concrete work, masonry work, wood work such as doors and windows, plumbing, flooring, waterproofing, finishing work like plastering, painting and distempering.

The Activity earthwork is segregated into different types depending on depth and type of soil. As for instance, an excavation of 1.5m deep in soft soil, an excavation of 3m deep in hard soil. Similarly, concrete work is segregated into several types on the basis of its mix proportions and its placement.

As for instance, M25 reinforced concrete is suitable in foundation, M30 reinforced concrete work in columns, slabs etc. Similarly, there are various small civil works in each construction project.

The construction project cost is estimated on the basis of each works related to each construction activity. Thus it is necessary to compute the cost of each small works.

Rate analysis of Civil Works or Building Works is the determination of cost of each construction work per unit quantity.

This cost includes the cost of materials, labors, machinery, contractors profit and other diverse insignificant expenses essential for the specific work that should be executed in unit quantity.

As for instance, cost of 1 cubic meter of M20 RCC work in slab, Cost of 1 cubic meter of excavation in soft soil of 1.5m depth, cost of 1 square meter of plastering of 20mm, cost of 1 square meter of painting work with specified paint in 2 layers or 3 layers as necessary.

Compute the cost of materials in rate analysis as composite of cost of material at origin, its transportation costs, taxes. The rate of labor is set with skill of the labor, like skilled labor, semi-skilled and unskilled labor. The cost of materials and labors differ from place to place. Thus, the cost of each construction work fluctuates from place to place.

How to create rate analysis of civil works

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Published By
Arka Roy

How to estimate the weight of a round shaped steel bar

In this construction video tutorial, you will learn the detailed method for estimating the weight of mild steel round bar with the plug chugging formula.

The formula is represented as W = D2/162.198xL
This formula is very useful in determining the weight of mild steel bar in Kg.

Here, D denotes dia of bar in mm and L denotes length of bar in meters.

In this video, a round shape cross section bar is selected and it’s length is taken as L and diameter is D.

Weight = Volume x Unit Weight

W = V x ꙍ (Volume = X-section area x length and omega is the unit weight of material)

As the bar is round, the cross sectional are will be πD2/4

So, putting the value we get the following:-

W = πD2/4 x L

For mild steel, unit weight is taken as 7850 kg/m3 or 222.32 kg/ft3

Putting the value, we get W = πD2/4 x L

= πD2/4 x L x 7850 = 6165.375583 x D2 x L/10002

= 6165.3755 x 10-3 x D2 x L

= 1/162.198 x D2 x L

So, W = D2/162.198 x L

To get more details, watch the following video tutorial.

Video Source: SL Khan

How to estimate the weight of a round shaped steel bar

Published By
Arka Roy

Online demonstration of QuickSuite 4.0 – A robust software for structural engineer

IES has developed QuickSuite 4.0, a powerful software for perfect structural design.

This product is comprised of four standalone tools which range from QuickRWall, QuickFooting, QuickMasonry, and QuickConcreteWall. These products can be set up collectively or any single product can be chosen for downloading as per your choice.

QuickRWall: QuickRWall is mostly recognized among structural engineers for designing retaining wall efficiently. It will facilitate the structural engineers to create superior quality wall design in quickest possible time. The reports are supported with full equations and intermediate data is instantly accessible for full checking. QuickRWall contains good graphical interface and very user-friendly.

Wall Configurations:

• Cantilever Retaining Walls
• Gravity Retaining Walls (ACI Chapter 22)
• Restrained Walls, Basement Walls, Propped Cantilevers
• Tapered (Battered) or Stepped

Wall Materials:

• Concrete,
• Masonry
• Mixed Concrete & Masonry

QuickConcreteWall: QuickConcreteWall is specifically designed for reinforced concrete shear walls and is considered as a handy tool for detailing a concrete wall depending on in-plane forces.

Complicated ACI interaction checks are accomplished instantly while adjusting design parameters and observe the results. Complete rebar detailing is provided in a productivity-quick format.

QuickFooting: Concrete spread footing (single column pad), is imported from VisualAnalysis. Design and examine reinforced concrete footings under a single column devoid of creating a complicated analysis model of the building.

It provides the following advantages :-

• Will verify different types of footings simultaneously (for worst case).
• Automatic sizing and detailing (optional).
• Advanced handling of biaxial loading
• Offset pedestal from footing center
• Checks footing, pedestal, and interface.
• Stability checks: Bearing pressure (net & gross), overturning, sliding, and uplift.
• Complete units flexibility.
• Perfect estimation of bearing pressure under biaxial loading.

QuickMasonry: It is an individual tool of masonry components that can deal with several structural components inside a single project file. The QuickMasonry “Project Management” tool is utilized to design a entire series of lintels and walls, for a single building in one project file, by adhering to the most updated masonry design specifications as well as a series of remarkable features.

The software deals with the following masonry components :-

• Lintels
• Bearing Walls
• Panel Walls (loads out of plane)
• Shear Walls
• Pilasters
• Columns
• Beams

Go through the following video to view the online demonstration of the software.

To download the software, go through the following link cesdb.com

Online demonstration of QuickSuite 4.0 – A robust software for structural engineer

Published By
Arka Roy

What are the variations among Cement vs Mortar

The variation among cement and mortar is that cement refers to the binding agent, while mortar is a product formed with cement, sand and lime.

Both these materials have separate objectives like cement becomes usable with water and creates a bond with other elements to shape one solid object, while mortar is effective for retaining bricks or stone jointly, and cannot remain detached like concrete. Cement is a material that is applicable to form mortar grout and concrete etc.

Each mortar can be utilized in different ways, grout or concrete blended with cement, like grout can fill gaps among tiles, but if the joints in the blocks contain missing sections, mortar should be applied. Cement comes in different categories like portland, white or masonry cement. The objective of Portland cement is to develop an object for structural usages.

Mortar may comprise of either Portland cement with lime, or masonry cement, lime and sand, accumulates masonry units into structural systems. The compressive and bond strength as well as the absorption capacity is obtained by the mix ratio of cement and the other constituents.

There are bonding enhancers in mortar which are utilized for close the gapping among stone, brick or concrete blocks throughout building. It is also applied for repairing and renovating purposes. Mortar is used as a compact paste, and it turns out to be rigid after a short span to make a firm seal among stones or bricks so that air and moisture can’t get into the structure. Mortar can be easily fixed with joint reinforcements, etc, in the bricks.

It contributes to construct a building with strong structure and elegant look. There are various types of mortars like Portland mortar formed with Portland cement, sand and water. Another type is known lime mortar that facilitates the moisture to proceed freely, and pass away from the surface. Mortar has good longevity devoid of persistent repairs. Mortar is formed by mixing cement with lime and sand whereas cement is formed by mixing with sand.

In brief:

1. Cement stands for a binding agent to develop mortar, concrete and grout.
2. Mortar is formed by adding water, sand and lime to cement.

3. Mortar is generally utilized for closing the gaps among bricks and stones to resist moisture from leaking in.
4. Cement comes in various forms like Portland, masonry cement etc.
5. There are various categories and colors of mortar like terracotta or white etc.

What are the variations among Cement vs Mortar

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Published By
Arka Roy